MITOCHONDRIA OF PLANT-LEAVES CONTAIN 2 THIOREDOXINS - COMPLETION OF THE THIOREDOXIN PROFILE OF HIGHER-PLANTS

The distribution of mitochondrial (mt) thioredoxins in plants has been analyzed. Mitochondria from spinach, soybean, and potato leaves conta in two different mt-thioredoxins in about equal amount whereas potato tuber mitochondria possess only one such protein. This pattern suggest s that a specific process, as yet unknown, of photoautotrophic metabol ism is linked to a thioredoxin system in green plant mitochondria, and another thioredoxin function (e.g., in regulating alpha-ketoacid dehy drogenase complexes) may be common in all mitochondria. The mt-thiored oxins described here can be differentiated from other leaf thioredoxin s. They are neither identical with chloroplast thioredoxins nor with t hioredoxin h preparations previously described.